Compaction bodies are usually mounted on vehicles and are provided with a compaction head or packer plate mounted in the body. The compaction head extends across the body and is movable lengthwise of the body for periodically compressing the material into the rear portion of the body as the material is collected. When the vehicle reaches the dumping site the material may be ejected or removed from the body by operation of the compaction head. The compaction head may be moved throughout the major portion of the length of the body and to varying degrees therein during the compaction action depending on the amount of material in the body. The head is normally located at the front portion of the compaction body when it is not in use. During discharge of material from the compaction body, the compaction head moves to the full extent to the rear of the compaction body.
In manual operation of vehicles of this type, the operator of the vehicle determines when it is desirable to compact or compress the material within the body. He manually initiates operation of the compaction head by movement of a hydraulic valve to provide fluid under pressure to a hydraulic cylinder which drives the head towards the rear of the body. When the compaction head reaches the point that the material is being compressed within the body, the operator then initiates a return stroke of the cylinder to return the compaction head towards its original position at the front of the compaction body. The degree of compaction of material within the compaction body determines the amount of material or payload that can be handled. Increasing the amount of compaction reduces the number of trips required by the vehicle between the point where the trash is collected and the dumping site where the material is discharged. The degree of compaction is related not only to the compaction pressure but also to the length of time the material is held under pressure. By holding the compaction head under pressure against the compacted material, the material will hold its compacted form to a higher degree than if the pressure is released without the holding period. With manual operation of the compaction head, the degree of compaction will vary from load to load and within a single load. To achieve consistent loading under manual operation, requires operator's attention which could be applied to other responsibilities, for example driving the vehicle to next location where refuse is to be collected.
Automatic operation of a packer head is difficult because of the varying length of travel of the compaction head and the need to manually interrupt a compaction cycle under various conditions. Mechanical limit switchers are not suitable for use in controlling the forward movement of the compaction head since refuse in the body would interfere with the operation of the switcher and the degree of movement will be different depending on the amount of refuse.
It is an object of this invention to improve operation of compaction bodies to provide better, more consistent, compaction of material and to reduce operator time in the compaction operation.
It is a further object of this invention to automate the operation of compaction heads in refuse compaction bodies.
It is a further object of this invention to provide automatic circuitry for the operation of compaction heads in refuse compaction bodies.